I recently received quotes from three different companies. Two of the companies said I needed a 5 ton system, while the other guy swears up and down I only need a 4 ton system.
Of the two who say I need a 5 ton system, only one did a heat load calculation. He showed me his worksheet.
The guy who says I need a 4 ton system didn't mention anything about a heat load calculation while he was here, although he did take awhile to put quotes together (like maybe a half an hour? Not nearly as long as the guy I saw take measurements) and he did go up into my attic. When I told him about the other guy who did a load calculation, he told me he did one as well (though it was never mentioned in any conversation). He said he did it on his computer and was skeptical when I mentioned that the other guy did it with a pencil/paper worksheet. I asked him to send me the heat load calculation and he has yet to do so.
For what it's worth, my house is roughly 2450 sf. It faces east. I have three large sliders that make up the majority of the backside of my house, but I also have a large back porch with a roof, so I don't get much sun or heat in the back of the house. The guy who showed me his calculations said he wrote up my sliders as having window tinting. They don't have it, but he said he wrote it up like that to take into account the shading I receive from my porch roof.
My current system is 18 years old and the info on it has worn off, so no one knows what I currently have.
What would you be inclined to think?